This year, it should be easy to figure out who's been naughty and who's been nice; people who feel like they're being watched are much more likely to be honest, psychologists at England's Newcastle University have discovered, than those who don't. While this may not in itself be a revolutionary concept, the way the docs conducted their experiment deserves mention.

There's a coffee cart at Newcastle University -- which operates on the honor system. People can help themselves, so long as they leave 50p for coffee or 30p for tea. For 10 weeks last Spring, they alternately hung two different posters above the coffee station: one depicting a cheerful bunch of flowers, the other a pair of staring eyes. They found that people were 2.76 times more likely to pay for their drinks while the eyes poster was hung; therefore, it seems that even the merest suggestion that someone is being watched -- as patently false as that suggestion may be -- is enough to change their behavior. Not only has the psychology community taken note, but the Birmingham police department has as well, slapping up posters of eyes all around their fair city, as part of a campaign called "We've got our eyes on criminals."